The prefrontal cortex (PFC) is vital to working memory. Disrupted functioning of the prefrontal cortex and a resulting decrease in working memory are seen in late stage Parkinson's disease and Schizophrenia. Exposing animals to environments that provide increased stimulation imparts resilience to cognitive deficits resulting from environmental or age related pathologies as well as aiding recovery from neural damage. In healthy animals, housing in enriched environmental conditions (EC) has resulted in superior performance of these over animals housed in isolated environmental conditions (IC) on many learning and memory paradigms, including tests of working memory. Neuroanatomy is greatly altered by enrichment, particularly within the neocortex. Most research to date on neurochemical differences between EC and IC animals has focused on cholinergic or monoamine systems; however, preliminary data suggests that mechanisms of glutamatergic transmission within the PFC are indeed altered by levels of environmental enrichment. As prefrontal glutamate (Glu) is involved in working memory circuitry, these modifications may, in part, result in the observed differences in working memory observed between housing groups. This study proposes to investigate the effects of differential housing on glutamatergic transmission within the PFC and the relationship of these changes to working memory.